Qt5 built in qwt (#570)

- qt4->qt5
- in built qt5 6.1.5 because rhel7 is not upto date with qt5, removed findqwt.cmake
- made a fix in qwt lib (qwt_plot_layout.h) to work with 5.15 and lower versions for qrect constr.
- qt5 forms fixed, qt4 many hard coding forms switched to forms including qtabwidget, scrolls etc, fonts moved to forms
 - docking option enabled by default, removed option to disable docking feature from "Mode"
- added qVersionResolve utility functions to handle compatibility before and after qt5.12
- qtplots (ian's code) takes in gain mode enable to set some settings within the class, with proper gain plot ticks
- ensure gain plots have no zooming of z axis in 2d and y axis in 1d
- removed placeholder text in qpalette in main window form as its not supportd until 5.12 (so using qt5.9 designer insted of qt5.15 to cope)
- tab order
Servers:
- fixed some error messages that were empty for fail in funcs (mostly minor as if this error, major issues)

slsDetectorGui/include/qTabPlot.h

@@ -38,8 +38,8 @@ class qTabPlot : public QWidget, private Ui::TabPlotObject {
     void CheckAspectRatio();
     void SetZRange();
     void SetStreamingFrequency();
-    void SetStreamingHwm(int value);
-    void SetReceivingHwm(int value);
+    void SelectHwm(int value);
+    void SetHwm(int value);
 
   signals:
     void DisableZoomSignal(bool);
@@ -50,8 +50,11 @@ class qTabPlot : public QWidget, private Ui::TabPlotObject {
     void Select1DPlot(bool enable);
     void GetGapPixels();
     void GetStreamingFrequency();
+    void GetHwm();
     void GetStreamingHwm();
+    void SetStreamingHwm(int value);
     void GetReceivingHwm();
+    void SetReceivingHwm(int value);
     void SetXYRange();
     void MaintainAspectRatio(int dimension);
 
@@ -66,6 +69,8 @@ class qTabPlot : public QWidget, private Ui::TabPlotObject {
     static QString defaultImageXAxisTitle;
     static QString defaultImageYAxisTitle;
     static QString defaultImageZAxisTitle;
+
+    enum { SND_HWM, RX_HWM };
 };
 
 } // namespace sls